diff --git a/renderdoc/driver/d3d12/d3d12_state.cpp b/renderdoc/driver/d3d12/d3d12_state.cpp
index 5d4b272ca..24fb89d83 100644
--- a/renderdoc/driver/d3d12/d3d12_state.cpp
+++ b/renderdoc/driver/d3d12/d3d12_state.cpp
@@ -109,6 +109,7 @@ void D3D12RenderState::ResolvePendingIndirectState(WrappedID3D12Device *device)
 
           if(comSig->sig.graphics)
           {
+            graphics.sigelems.resize_for_index(arg.Constant.RootParameterIndex);
             graphics.sigelems[arg.Constant.RootParameterIndex].constants.resize_for_index(
                 arg.Constant.Num32BitValuesToSet + arg.Constant.DestOffsetIn32BitValues);
             graphics.sigelems[arg.Constant.RootParameterIndex].SetConstants(
@@ -116,6 +117,7 @@ void D3D12RenderState::ResolvePendingIndirectState(WrappedID3D12Device *device)
           }
           else
           {
+            compute.sigelems.resize_for_index(arg.Constant.RootParameterIndex);
             compute.sigelems[arg.Constant.RootParameterIndex].constants.resize_for_index(
                 arg.Constant.Num32BitValuesToSet + arg.Constant.DestOffsetIn32BitValues);
             compute.sigelems[arg.Constant.RootParameterIndex].SetConstants(